what do i do wgen she talks to me?

Okay so there is a toxic friend who I don't wanna be friends with as she Is toxic . I tried talking to her and she got angry and told me to p off I have screenshots and then I thought I should give her the silent treatment or just not talk yo her but she waits fir ne after my lesson so we can walk together as she is in my lesson and then she comes to me at lunch time . My parents told me not to talk to her so what do I do when she cones to talk to me ?? Also what if she tells the teacher a lie about me like I've done something when I haven't really??? I'm not getting teachers involved BC it's got nothing to do with them but wat if she does snitch a lie about me